Switching Method, Network Device and Terminal Device

ABSTRACT

A handover method, a network device, and a terminal device are provided. The method includes: a first network device acquires measurement results of links, wherein the links include a link between the first network device and a first terminal device and a link between the first network device and a second terminal device; and the first network device determines at least one of a first handover scheme of the first terminal device, or a second handover scheme of the second terminal device according to the measurement results.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a 371 application of International Application No.PCT/CN2017/077926, filed on Mar. 23, 2017, the entire disclosure ofwhich is hereby incorporated by reference.

TECHNICAL FIELD

Implementations of the present disclosure relate to the field ofwireless communication, and more particularly relate to a handovermethod, a network device, and a terminal device.

BACKGROUND

In an existing wireless communication system, a Remote User Equipment(Remote UE), such as a wearable device, may transmit data through aRelay User Equipment (Relay UE), such as an existing common mobile phoneuser equipment. As shown in FIG. 1, a Relay UE may help a Remote UE tocomplete data transmission. As shown in FIG. 2A and FIG. 2B, a Relay UEand a Remote UE may establish a control plane connection through thesame base station or different base stations, while the Relay UE helpsthe Remote UE to complete data forwarding. At this time, if the Relay UEor the Remote UE moves, the base station(s) will be required to carryout handover to ensure continuity of data transmission.

However, in practical applications, a Relay UE and a Remote UE arelikely to be in the same location, e.g. both on a user. At this time,both the Relay UE and the Remote UE are likely to move in the samedirection and at the same speed at the same time. If cell handover isrequired in the moving process, currently, a base station usually handsover the two UEs separately. As such, if the two UEs are handed over tocells covered by different base stations, relay transmission between theRelay UE and the Remote UE will be greatly affected.

SUMMARY

The implementations of the present disclosure provide a handover method,a network device.

In a first aspect, there is provided a handover method, including:acquiring, by a first network device, measurement results of links,wherein the links include a link between the first network device and afirst terminal device and a link between the first network device and asecond terminal device; and determining, by the first network device, afirst handover scheme of the first terminal device and/or a secondhandover scheme of the second terminal device according to themeasurement results.

Optionally, in one implementation of the first aspect, the links furtherinclude a link between the first terminal device and the second terminaldevice.

Optionally, in one implementation of the first aspect, determining, bythe first network device, the first handover scheme of the firstterminal device and/or the second handover scheme of the second terminaldevice according to the measurement results, includes: determining, bythe first network device, the first handover scheme and/or the secondhandover scheme according to states of the first terminal device and thesecond terminal device and the measurement results.

Optionally, in one implementation of the first aspect, if the firstterminal device is in a connected state, the first handover schemeincludes that the first terminal device is handed over from a cellcovered by the first network device to a cell covered by the secondnetwork device, or the first terminal device does not perform cellhandover; if the first terminal device is in an inactive state or anidle state, the first handover scheme includes that the first terminaldevice reselects a cell covered by the second network device as a cellto be accessed, or the first terminal device does not perform cellreselection; if the second terminal device is in a connected state, thesecond handover scheme includes that the second terminal device ishanded over from a cell covered by the first network device to a cellcovered by the second network device or a cell covered by anothernetwork device, or the second terminal device does not perform cellhandover; if the second terminal device is in an inactive state or anidle state, the second handover scheme includes that the second terminaldevice reselects a cell covered by the second network device or a cellcovered by another network device as a cell to be accessed, or thesecond terminal device does not perform cell reselection.

Optionally, in one implementation of the first aspect, determining, bythe first network device, the first handover scheme of the firstterminal device and/or the second handover scheme of the second terminaldevice according to the measurement results, includes: determining, bythe first network device, whether a link connection between the firstterminal device and the second terminal device is maintained accordingto the measurement results; and determining, by the first networkdevice, the first handover scheme and/or the second handover schemeaccording to whether the link connection between the first terminaldevice and the second terminal device is maintained.

Optionally, in one implementation of the first aspect, if the firstnetwork device determines that the link connection between the firstterminal device and the second terminal device is maintained, after thefirst terminal device performs the first handover scheme and the secondterminal device performs the second handover scheme, the first terminaldevice and the second terminal device are located in a cell covered by asame network device.

Optionally, in one implementation of the first aspect, the methodfurther includes: determining, by the first network device, whether alink connection between the first terminal device and the secondterminal device is maintained according to the measurement results; ifthe first network device determines that the link connection between thefirst terminal device and the second terminal device is not maintained,the method further includes: sending, by the first network device,release indication information to the first terminal device, wherein therelease indication information is used for instructing the firstterminal device to release the link connection with the second terminaldevice.

Optionally, in one implementation of the first aspect, before the firstnetwork device determines the first handover scheme of the firstterminal device and/or the second handover scheme of the second terminaldevice according to the measurement results, the method furtherincludes: acquiring, by the first network device, associationinformation between the first terminal device and the second terminaldevice, wherein the association information includes a pairingrelationship or a connection relationship between the first terminaldevice and the second terminal device; determining, by the first networkdevice, the first handover scheme of the first terminal device and/orthe second handover scheme of the second terminal device according tothe measurement results, includes: determining, by the first networkdevice, the first handover scheme and/or the second handover schemeaccording to the association information and the measurement results.

Optionally, in one implementation of the first aspect, if the firsthandover scheme includes that the first terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device, the method further includes: sending, by thefirst network device, a handover request message to the second networkdevice, wherein the handover request message is used for indicating thatthe first terminal device requests performing the first handover scheme;and receiving, by the first network device, a handover command sent bythe second network device according to the handover request message,wherein the handover command includes a resource for cell handover ofthe first terminal device.

Optionally, in one implementation of the first aspect, the handoverrequest message includes association information between the firstterminal device and the second terminal device.

Optionally, in one implementation of the first aspect, if the secondhandover scheme includes that the second terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device, the handover request message is further used forindicating that the second terminal device requests performing thesecond handover scheme, and the handover command further includes aresource for cell handover of the second terminal device.

Optionally, in one implementation of the first aspect, if the secondhandover scheme includes that the second terminal device reselects acell covered by the second network device or a cell covered by anothernetwork device as a cell to be accessed, the handover request message isfurther used for indicating that the second terminal device requestsperforming the second handover scheme, and the handover command furtherincludes information on whether the second terminal device is allowed toperform cell reselection.

Optionally, in one implementation of the first aspect, if the secondnetwork device allows the second terminal device to perform cellreselection, the handover command further includes information of a cellto be accessed reselected by the second terminal device.

Optionally, in one implementation of the first aspect, the firstterminal device is a Relay UE and the second terminal device is a RemoteUE; or the first terminal device is a Remote UE and the second terminaldevice is a Relay UE.

Optionally, in one implementation of the first aspect, the measurementresult of a link includes a measurement result of a link quality of thelink and/or a measurement result of a link state of the link.

Optionally, in one implementation of the first aspect, acquiring, by thefirst network device, the measurement results of the links, includes:receiving, by the first network device, the measurement results sent bythe first terminal device; or receiving, by the first network device, ameasurement result of a link between the first terminal device and thefirst network device sent by the first terminal device, and receiving ameasurement result of a link between the second terminal device and thefirst network device sent by the second terminal device.

Optionally, in one implementation of the first aspect, acquiring, by thefirst network device, the measurement results of the links, includes:receiving, by the first network device, a measurement result of a linkbetween the first terminal device and the second terminal device sent bythe first terminal device or the second terminal device.

Optionally, in one implementation of the first aspect, acquiring, by thefirst network device, the measurement results of the links, includes:acquiring, by the first network device, a measurement result of a linkcarried in an adaptation layer or a direct connection interface protocolstack PC5 sent by the first terminal device or the second terminaldevice.

In a second aspect, there is provided a handover method, including:acquiring, by a first terminal device, measurement results of links,wherein the links include a link between the first terminal device and afirst network device and a link between the first network device and asecond terminal device; sending, by the first terminal device, themeasurement results to the first network device, wherein the measurementresults are used for the first network device to determine a firsthandover scheme of the first terminal device; and receiving, by thefirst terminal device, a handover command and performing the firsthandover scheme according to the handover command.

Optionally, in one implementation of the second aspect, the linksfurther include a link between the first terminal device and the secondterminal device.

Optionally, in one implementation of the second aspect, the firsthandover scheme includes that the first terminal device is handed overfrom a cell covered by the first network device to a cell covered by asecond network device, or the first terminal device does not performcell handover.

Optionally, in one implementation of the second aspect, if the firstnetwork device determines that a link connection between the firstterminal device and the second terminal device is maintained, after thefirst terminal device performs the first handover scheme, the firstterminal device and the second terminal device are located in a cellcovered by a same network device.

Optionally, in one implementation of the second aspect, if the firstnetwork device determines that a link connection between the firstterminal device and the second terminal device is not maintained, themethod further includes: receiving, by the first terminal device,release indication information, and releasing, by the first terminaldevice, the link connection with the second terminal device according tothe release indication information.

Optionally, in an implementation of the second aspect, the methodfurther includes: acquiring, by the first terminal device, associationinformation between the first terminal device and the second terminaldevice, wherein the association information includes a pairingrelationship or a connection relationship between the first terminaldevice and the second terminal device; and sending, by the firstterminal device, the association information to the first networkdevice, and the first network device determines the first handoverscheme according to the association information and the measurementresults.

Optionally, in one implementation of the second aspect, if the firsthandover scheme includes that the first terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device, the handover command further includes a resourcefor cell handover of the first terminal device.

Optionally, in one implementation of the second aspect, the firstterminal device is a Relay UE and the second terminal device is a RemoteUE; or the first terminal device is a Remote UE and the second terminaldevice is a Relay UE.

Optionally, in one implementation of the second aspect, the measurementresult of a link includes a measurement result of a link quality of thelink and/or a measurement result of a link state of the link.

Optionally, in one implementation of the second aspect, acquiring, bythe first terminal device, the measurement results of the links,includes: determining, by the first terminal device, a measurementresult of a link between the first terminal device and the first networkdevice, and receiving a measurement result of a link between the firstnetwork device and the second terminal device sent by the secondterminal device.

Optionally, in one implementation of the second aspect, acquiring, bythe first terminal device, the measurement results of the links,includes: determining, by the first terminal device, a measurementresult of a link between the first terminal device and the secondterminal device; or receiving, by the first terminal device, ameasurement result of a link between the first terminal device and thesecond terminal device sent by the second terminal device.

Optionally, in one implementation of the second aspect, acquiring, bythe first terminal device, the measurement results of the links,includes: acquiring, by the first terminal device, a measurement resultof a link carried in an adaptation layer or a direct connectioninterface protocol stack PC5 sent by the second terminal device.

In a third aspect, there is provided a handover method, including:acquiring, by a second terminal device, a measurement result of a link,wherein the link includes a link between the second terminal device anda first network device; sending, by the second terminal device, themeasurement result to the first network device through a first terminaldevice, wherein the measurement result is used for the first networkdevice to determine a second handover scheme of the second terminaldevice; and receiving, by the second terminal device, a handover commandand performing the second handover scheme according to the handovercommand.

Optionally, in one implementation of the third aspect, the link furtherincludes a link between the first terminal device and the secondterminal device.

Optionally, in one implementation of the third aspect, the secondhandover scheme includes that the second terminal device reselects acell covered by the second network device as a cell to be accessed, orthe second terminal device does not perform cell reselection.

Optionally, in one implementation of the third aspect, if the firstnetwork device determines that a link connection between the firstterminal device and the second terminal device is maintained, after thesecond terminal device performs the second handover scheme, the firstterminal device and the second terminal device are located in a cellcovered by a same network device.

Optionally, in one implementation of the third aspect, if the firstnetwork device determines that there is no need to maintain a linkconnection between the second terminal device and the first terminaldevice, the method further includes: receiving, by the second terminaldevice, release indication information and releasing the link connectionwith the first terminal device according to the release indicationinformation.

Optionally, in one implementation of the third aspect, if the secondhandover scheme includes that the second terminal device reselects acell covered by the second network device as a cell to be accessed, thehandover command further includes information of a cell to be accessedreselected by the second terminal device.

Optionally, in one implementation of the third aspect, the firstterminal device is a Relay UE and the second terminal device is a RemoteUE; or the first terminal device is a Remote UE and the second terminaldevice is a Relay UE.

Optionally, in one implementation of the third aspect, the measurementresult of a link includes a measurement result of a link quality of thelink and/or a measurement result of a link state of the link.

Optionally, in one implementation of the third aspect, sending, by thesecond terminal device, the measurement result to the first networkdevice through the first terminal device, includes: sending, by thesecond terminal device, the measurement result carried in an adaptationlayer or a direct connection interface protocol stack PC5 to the firstnetwork device through the first terminal device.

Optionally, in one implementation of the third aspect, receiving, by thesecond terminal device, the handover command includes: receiving, by thesecond terminal device, the handover command sent by the first terminaldevice; or receiving, by the second terminal device, the handovercommand sent by the first network device through a paging message.

In a fourth aspect, there is provided a handover method, including:receiving, by a second network device, a handover request message sentby a first network device, wherein the handover request message is usedfor indicating that a first terminal device requests performing a firsthandover scheme and a second terminal device requests for performing asecond handover scheme; and sending, by the second network device, ahandover command to the first network device according to the handoverrequest message.

Optionally, in one implementation of the fourth aspect, if the firstterminal device is in a connected state, the first handover schemeincludes that the first terminal device is handed over from a cellcovered by the first network device to a cell covered by a secondnetwork device, or the first terminal device does not perform cellhandover; if the first terminal device is in an inactive state or anidle state, the first handover scheme includes that the first terminaldevice reselects a cell covered by the second network device as a cellto be accessed, or the first terminal device does not perform cellreselection; if the second terminal device is in a connected state, thesecond handover scheme includes that the second terminal device ishanded over from a cell covered by the first network device to a cellcovered by the second network device or a cell covered by anothernetwork device, or the second terminal device does not perform cellhandover; if the second terminal device is in an inactive state or anidle state, the second handover scheme includes that the second terminaldevice reselects a cell covered by the second network device or a cellcovered by another network device as a cell to be accessed, or thesecond terminal device does not perform cell reselection.

Optionally, in one implementation of the fourth aspect, if the firsthandover scheme includes that the first terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device, the handover command includes a resource for cellhandover of the first terminal device.

Optionally, in one implementation of the fourth aspect, if the secondhandover scheme includes that the second terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device, the handover command further includes a resourcefor cell handover of the second terminal device.

Optionally, in one implementation of the fourth aspect, if the secondhandover scheme includes that the second terminal device reselects acell covered by the second network device as a cell to be accessed, thehandover command further includes information on whether the secondterminal device is allowed to perform cell reselection.

Optionally, in one implementation of the fourth aspect, if the secondnetwork device allows the second terminal device to perform cellreselection, the handover command further includes information of a cellto be accessed reselected by the second terminal device.

Optionally, in one implementation of the fourth aspect, the firstterminal device is a Relay UE and the second terminal device is a RemoteUE; or the first terminal device is a Remote UE and the second terminaldevice is a Relay UE.

In a fifth aspect, there is provided a network device that may performoperations of the network device in the first aspect or any optionalimplementation of the first aspect. Specifically, the network device mayinclude modules used for performing operations of the network device inthe first aspect or any possible implementation of the first aspect.

In a sixth aspect, there is provided a terminal device that may performoperations of the terminal device in the second aspect or any optionalimplementation of the second aspect. Specifically, the terminal devicemay include modules used for performing operations of the terminaldevice in the second aspect or any possible implementation of the secondaspect.

In a seventh aspect, there is provided a terminal device that mayperform operations of the terminal device in the third aspect or anyoptional implementation of the third aspect. Specifically, the terminaldevice may include modules used for performing operations of theterminal device in the third aspect or any possible implementation ofthe third aspect.

In an eighth aspect, there is provided a network device that may performoperations of the network device in the fourth aspect or any optionalimplementation of the fourth aspect. Specifically, the network devicemay include modules used for performing operations of the network devicein the fourth aspect or any possible implementation of the fourthaspect.

In a ninth aspect, there is provided a network device. The networkdevice includes: a processor, a transceiver, and a memory. Theprocessor, the transceiver, and the memory communicate with each otherthrough an internal connection path. The memory is used for storinginstructions, and the processor is used for executing the instructionsstored in the memory. When the processor executes the instructionsstored in the memory, the execution causes the network device to executethe method in the first aspect or any possible implementation of thefirst aspect, or the execution causes the network device to implementthe network device provided in the fifth aspect.

In a tenth aspect, there is provided a terminal device. The terminaldevice includes: a processor, a transceiver, and a memory. Theprocessor, the transceiver, and the memory communicate with each otherthrough an internal connection path. The memory is used for storinginstructions, and the processor is used for executing the instructionsstored in the memory. When the processor executes the instructionsstored in the memory, the execution causes the terminal device toexecute the method in the second aspect or any possible implementationof the second aspect, or the execution causes the terminal device toimplement the terminal device provided in the sixth aspect.

In an eleventh aspect, there is provided a terminal device. The terminaldevice includes: a processor, a transceiver, and a memory. Theprocessor, the transceiver, and the memory communicate with each otherthrough an internal connection path. The memory is used for storinginstructions, and the processor is used for executing the instructionsstored in the memory. When the processor executes the instructionsstored in the memory, the execution causes the terminal device toexecute the method in the third aspect or any possible implementation ofthe third aspect, or the execution causes the terminal device toimplement the terminal device provided in the seventh aspect.

In a twelfth aspect, there is provided a network device. The networkdevice includes: a processor, a transceiver, and a memory. Theprocessor, the transceiver, and the memory communicate with each otherthrough an internal connection path. The memory is used for storinginstructions, and the processor is used for executing the instructionsstored in the memory. When the processor executes the instructionsstored in the memory, the execution causes the network device to executethe method in the fourth aspect or any possible implementation of thefourth aspect, or the execution causes the network device to implementthe network device provided in the eighth aspect.

In a thirteenth aspect, there is provided a computer-readable storagemedium storing a program that causes a network device to perform any onehandover method of the first aspect and various implementations thereof.

In a fourteenth aspect, there is provided a computer-readable storagemedium storing a program that causes a terminal device to perform anyone handover method of the second aspect and various implementationsthereof.

In a fifteenth aspect, there is provided a computer-readable storagemedium storing a program that causes a terminal device to perform anyone handover method of the third aspect and various implementationsthereof.

In a sixteenth aspect, there is provided a computer-readable storagemedium storing a program that causes a network device to perform any onehandover method of the fourth aspect and various implementationsthereof.

In a seventeenth aspect, there is provided a system chip, which includesan input interface, an output interface, a processor, and a memory,wherein the processor is used for executing instructions stored in thememory, and when the instructions are executed, the processor mayimplement any one method in the first aspect and various implementationsthereof.

In an eighteenth aspect, there is provided a system chip, which includesan input interface, an output interface, a processor, and a memory,wherein the processor is used for executing instructions stored in thememory, and when the instructions are executed, the processor mayimplement any one method in the second aspect and variousimplementations thereof.

In a nineteenth aspect, there is provided a system chip, which includesan input interface, an output interface, a processor, and a memory,wherein the processor is used for executing instructions stored in thememory, and when the instructions are executed, the processor mayimplement any one method in the third aspect and various implementationsthereof.

In a twentieth aspect, there is provided a system chip, which includesan input interface, an output interface, a processor, and a memory,wherein the processor is used for executing instructions stored in thememory, and when the instructions are executed, the processor mayimplement any one method in the fourth aspect and variousimplementations thereof.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of relay transmission of a terminal devicein the prior art.

FIG. 2A is a schematic diagram of relay transmission of a terminaldevice in the prior art.

FIG. 2B is a schematic diagram of relay transmission of a terminaldevice in the prior art.

FIG. 3 is a schematic diagram of architecture of an application scenarioaccording to an implementation of the present disclosure.

FIG. 4 is a schematic flow chart of a handover method according to animplementation of the present disclosure.

FIG. 5 is a schematic flow chart of a handover method according to animplementation of the present disclosure.

FIG. 6 is a schematic flow chart of a handover method according to animplementation of the present disclosure.

FIG. 7 is a schematic flow chart of a handover method according to animplementation of the present disclosure.

FIG. 8 is a diagram of an interaction flow of a handover methodaccording to an implementation of the present disclosure.

FIG. 9 is a diagram of an interaction flow of a handover methodaccording to an implementation of the present disclosure.

FIG. 10 is a schematic block diagram of a network device according to animplementation of the present disclosure.

FIG. 11 is a schematic block diagram of a terminal device according toan implementation of the present disclosure.

FIG. 12 is a schematic block diagram of a terminal device according toan implementation of the present disclosure.

FIG. 13 is a schematic block diagram of a network device according to animplementation of the present disclosure.

FIG. 14 is a schematic diagram of structure of a network deviceaccording to an implementation of the present disclosure.

FIG. 15 is a schematic diagram of structure of a terminal deviceaccording to an implementation of the present disclosure.

FIG. 16 is a schematic diagram of structure of a terminal deviceaccording to an implementation of the present disclosure.

FIG. 17 is a schematic diagram of structure of a network deviceaccording to an implementation of the present disclosure.

FIG. 18 is a schematic diagram of structure of a system chip accordingto an implementation of the present disclosure.

DETAILED DESCRIPTION

Hereinafter, technical solutions in the implementations of the presentdisclosure will be described with reference to the accompanyingdrawings.

It should be understood that the technical solutions of theimplementations of the present disclosure may be applied to variouscommunication systems, such as a Global System of Mobile Communication(GSM) system, a Code Division Multiple Access (CDMA) system, a WidebandCode Division Multiple Access (WCDMA) system, a Long Term Evolution(LTE) system, a LTE Frequency Division Duplex (FDD) system, a LTE TimeDivision Duplex (TDD) system, a Universal Mobile TelecommunicationSystem (UMTS), and a future 5G communication system.

Various implementations are described herein in connection with terminaldevices in the present disclosure. The terminal devices may be referredto as user equipment (UE), access terminals, subscriber units,subscriber stations, mobile stations, mobile platforms, remote stations,remote terminals, mobile devices, user terminals, terminals, wirelesscommunication devices, user agents or user devices. The access terminalmay be a cellular phone, a cordless phone, a session initiation protocol(SIP) phone, a wireless local loop (WLL) station, a personal digitalauxiliary (PDA), a handheld device with a wireless communicationfunction, a computing device or other processing device connected to awireless modem, a vehicle-mounted device, a wearable device, a terminaldevice in a future 5G network, or a terminal device in a future evolvingpublic land mobile network (PLMN), etc.

Various implementations are described herein in connection with networkdevices in the present disclosure. A network device may be a device forcommunicating with a terminal device, such as a base station (BaseTransceiver Station, referred to as “BTS”) in a GSM system or CDMA, abase station (NodeB, referred to as “NB”) in a WCDMA system, or anevolved base station (Evolutional Node B, referred to as “eNB” or“eNodeB”) in a LTE system, or the network device may be a relay station,an access point, a vehicle-mounted device, a wearable device, a networkside device in a future 5G network, or a network side device in a futureevolved PLMN network, etc.

FIG. 3 is a schematic diagram of an application scenario of animplementation of the present disclosure. A communication system in FIG.3 may include a network device 10, a network device 20, a terminaldevice 30, and a terminal device 40. The network device 10 is used forproviding communication services for the terminal device 30 and theterminal device 40. The terminal device 40 is a Remote UE such as awatch, and the terminal device 30 is a Relay UE such as a mobile phone.The terminal device 40 may perform data transmission with the networkdevice 10 through the terminal device 30. If the terminal device 30 andthe terminal device 40 are located at the same location, for example, ona user, the two terminal devices will move in the same direction and atthe same speed at the same time. If cell handover is required during themoving process, if the two terminal devices are handed over to cellscovered by different network devices, relay transmission between theRelay UE and the Remote UE will be greatly affected. Therefore, whenperforming cell handover during the moving process of the two terminaldevices, it is desirable for the terminal device 30 and the terminaldevice 40 to be handed over to a cell covered by the same networkdevice. As shown in FIG. 3, the terminal device 30 and the terminaldevice 40 are handed over by the network device 10 to a cell covered bythe network device 20, and then the terminal device 30 and the terminaldevice 40 may effectively perform normal relay transmission. Arrowsshown in FIG. 3 may represent uplink/downlink transmission throughcellular links between the terminal device 20 and the network device 10.

The network in the implementation of the present disclosure may refer toa Public Land Mobile Network (PLMN) or a device-to-device (D2D) networkor a machine-to-machine/man (M2M) network or other networks. FIG. 3 is asimplified schematic diagram of an example, and other terminal devicesmay be included in the network and are not shown in FIG. 3.

FIG. 4 is a schematic flowchart of a handover method 400 according to animplementation of the present disclosure. The method may be performed bya first network device such as the network device 10 in FIG. 3. As shownin FIG. 4, the handover method includes acts 410 and 420.

In 410, a first network device acquires measurement results of links,and the links include a link between the first network device and afirst terminal device and a link between the first network device and asecond terminal device.

In 420, the first network device determines a first handover scheme ofthe first terminal device and/or a second handover scheme of the secondterminal device according to the measurement results.

Optionally, at least one terminal device of the first terminal deviceand the second terminal device is in a connected state.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE, or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

Specifically, when the first terminal device and the second terminaldevice perform cell handover, the first network device may acquire ameasurement result of a link between the first network device and thefirst terminal device and a measurement result of a link between thefirst network device and the second terminal device, and the measurementresults of these links may be used to determine a first handover schemefor the first terminal device and a second handover scheme for thesecond terminal device. Since the first network device simultaneouslyacquires the measurement result of the link between the first terminaldevice and the first network device and the measurement result of thelink between the second terminal device and the first network device,the first network device may comprehensively consider measurementresults of multiple links when determining respective handover schemesfor the first terminal device and the second terminal device, and try toselect a cell covered by a same network device as a cell to be handedover to or a reselected cell to be accessed for the first terminaldevice and the second terminal device.

For example, if there is service data interaction between the firstterminal device and the second terminal device, when cell handover isrequired in moving processes of the two terminal devices, the firstnetwork device will try to select a cell covered by an identical networkdevice as a cell to be handed over to for the first terminal device andthe second terminal device according to measurement results whendetermining a first handover scheme and a second handover scheme toensure continuity of services of the terminal devices, although a signalintensity after handover is not optimal.

Optionally, the measurement results of the links acquired by the firstnetwork device may further include a measurement result of a linkbetween the first terminal device and the second terminal device.

In other words, the first network device may not only acquire ameasurement result of a link between the first network device and thefirst terminal device and a measurement result of a link between thefirst network device and the second terminal device, but also acquire ameasurement result of a link between the first terminal device and thesecond terminal device, and determine a first handover scheme and asecond handover scheme by comprehensively considering the measurementresults of the three links. Since a link condition between the twoterminal devices is considered, the two terminal devices may be tried tobe handed over to a cell covered by an identical network device whennecessary.

Optionally, the measurement result of a link includes a measurementresult of a link quality of the link and/or a measurement result of alink state of the link.

Since the first terminal device may determine measurement results oflinks of the first terminal device, that is, a measurement result of alink between the first terminal device and the first network device, anda measurement result of a link between the first terminal device and thesecond terminal device, and the second terminal device may determinemeasurement results of links of the second terminal device, that is, ameasurement result of a link between the second terminal device and thefirst network device, and a measurement result of a link between thesecond terminal device and the first terminal device, optionally, in410, the first network device receives the measurement resultstransmitted by the first terminal device, or the first network devicereceives a measurement result of a link between the first terminaldevice and the first network device transmitted by the first terminaldevice and receives a measurement result of a link between the secondterminal device and the first network device transmitted by the secondterminal device.

Further, the first network device acquiring the measurement results ofthe links may further include: the first network device receiving ameasurement result of a link between the first terminal device and thesecond terminal device transmitted by the first terminal device or thesecond terminal device.

Optionally, the first network device acquires the measurement results ofthe links, including: the first network device acquires a measurementresult of a link carried in an adaptation layer or a direct connectioninterface protocol stack PC5 sent by the first terminal device or thesecond terminal device.

That is, information of interaction such as measurement results amongthe first terminal device, the second terminal device, and the firstnetwork device may be carried in an adaptation layer or in a signalingor data of an existing direct connection interface protocol stack PC5.

Optionally, in 410, the first network device determines the firsthandover scheme of the first terminal device and/or the second handoverscheme of the second terminal device according to the measurementresults, including: the first network device determines the firsthandover scheme and/or the second handover scheme according to states inwhich the first terminal device and the second terminal device arelocated and the measurement results.

Optionally, if the first terminal device is in a connected state, thefirst handover scheme includes that the first terminal device is handedover from a cell covered by the first network device to a cell coveredby the second network device, or the first terminal device does notperform cell handover; if the first terminal device is in an inactivestate or an idle state, the first handover scheme includes that thefirst terminal device reselects a cell covered by the second networkdevice as a cell to be accessed, or the first terminal device does notperform cell reselection; if the second terminal device is in aconnected state, the second handover scheme includes that the secondterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device or a cell coveredby another network device, or the second terminal device does notperform cell handover; if the second terminal device is in an inactivestate or an idle state, the second handover scheme includes that thesecond terminal device reselects a cell covered by the second networkdevice or a cell covered by another network device as a cell to beaccessed, or the second terminal device does not perform cellreselection.

Here, if the first handover scheme causes the first terminal device tobe handed over to or reselect a cell covered by the second networkdevice, the second handover scheme may cause the second terminal deviceto be handed over to or reselect a cell covered by the same networkdevice as the first terminal device, i.e., the second network device,but if a condition of a signal intensity is not allowed, or the firstterminal device and the second terminal device do not need to maintain alink connection, should not maintain a link connection or are notsuitable to continue to maintain a link connection, the second terminaldevice may be handed over to a cell covered by another network device orreselect a cell covered by another network device as a cell to beaccessed.

Optionally, the first network device determines the first handoverscheme of the first terminal device and/or the second handover scheme ofthe second terminal device according to the measurement results,including: the first network device determines whether a link connectionbetween the first terminal device and the second terminal device ismaintained according to the measurement results; and the first networkdevice determines the first handover scheme and/or the second handoverscheme according to whether the link connection between the firstterminal device and the second terminal device is maintained.

Further, if the first network device determines that the link connectionbetween the first terminal device and the second terminal device ismaintained, after the first terminal device performs the first handoverscheme and the second terminal device performs the second handoverscheme, the first terminal device and the second terminal device arelocated in a cell covered by a same network device.

Specifically, if the first network device determines that the linkconnection between the first terminal device and the second terminaldevice is maintained, for example, the first network device determinesthat the link connection between the first terminal device and thesecond terminal device should be maintained, or the link connectionneeds to be maintained continuously, the first handover scheme and/orthe second handover scheme determined by the first network device willenable the first terminal device and the second terminal device to belocated in a cell covered by a same network device after the firstterminal device performs the first handover scheme and the secondterminal device performs the second handover scheme.

If the first network device determines that the link connection betweenthe first terminal device and the second terminal device is notmaintained, for example, the first network device determines that thelink connection between the first terminal device and the secondterminal device should not be maintained, or that the link connectiondoes not need to be maintained, or that a signal intensity cannot meet alink requirement between the first terminal device and the secondterminal device, then the first handover scheme and/or the secondhandover scheme determined by the first network device may enable thefirst terminal device and the second terminal device to be located in acell covered by a same network device or in cells covered by differentnetwork devices after the first terminal device performs the firsthandover scheme and the second terminal device performs the secondhandover scheme.

Optionally, the method further includes: the first network devicedetermines whether a link connection between the first terminal deviceand the second terminal device is maintained according to themeasurement results; if the first network device determines that thelink connection between the first terminal device and the secondterminal device is not maintained, the method further includes: thefirst network device sends release indication information to the firstterminal device, and the release indication information is used forinstructing the first terminal device to release the link connectionwith the second terminal device.

Optionally, before the act 420, that is, before the first network devicedetermines the first handover scheme of the first terminal device and/orthe second handover scheme of the second terminal device according tothe measurement results, the method further includes: the first networkdevice acquires association information between the first terminaldevice and the second terminal device, wherein the associationinformation includes a pairing relationship or a connection relationshipbetween the first terminal device and the second terminal device.

The first network device determines the first handover scheme of thefirst terminal device and/or the second handover scheme of the secondterminal device according to the measurement results, including: thefirst network device determines the first handover scheme and/or thesecond handover scheme according to the association information and themeasurement results.

Specifically, the first network device may determine the first handoverscheme and/or the second handover scheme according to the pairingrelationship or connection relationship between the first terminaldevice and the second terminal device and the measurement results of thelinks. For example, if the first terminal device and the second terminaldevice are in a connection relationship and have data interaction, thenwhen determining the first handover scheme and/or the second handoverscheme, the first network device will try to select a cell covered by anidentical network device as a cell to be handed over to or a reselectedcell to be accessed for the first terminal device and the secondterminal device according to the measurement results, although a signalintensity after handover is not optimal.

Optionally, if the first handover scheme includes that the firstterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the methodfurther includes: the first network device sends a handover requestmessage to the second network device, wherein the handover requestmessage is used for indicating that the first terminal device requestsperforming the first handover scheme; the first network device receivesa handover command sent by the second network device according to thehandover request message, and the handover command includes a resourcefor cell handover of the first terminal device.

After receiving the handover command, the first network device may givea handover instruction to the first terminal device, so that the firstterminal device is handed over to a cell covered by the second networkdevice according to the resource configured by the second network devicefor the first terminal device for cell handover.

The handover request message may include association information betweenthe first terminal device and the second terminal device and/or acontext of the first terminal device.

The association information may be used by the second network device todetermine whether the first terminal device is allowed to be handed overto a cell covered by the second network device, and if so, a handovercommand is issued, wherein the resource configured for the firstterminal device for cell handover is carried in the handover command.

Optionally, if the second handover scheme includes that the secondterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handoverrequest message is further used for indicating that the second terminaldevice requests performing the second handover scheme, and the handovercommand further includes a resource for cell handover of the secondterminal device.

After receiving the handover command, the first network device may givea handover instruction to the second terminal device to enable thesecond terminal device to be handed over to a cell covered by the secondnetwork device according to the resource configured by the secondnetwork device for the second terminal device for cell handover.

The handover request message may further include a context of the secondterminal device.

Optionally, if the second handover scheme includes that the secondterminal device reselects a cell covered by the second network device ora cell covered by another network device as a cell to be accessed, thehandover request message is further used for indicating that the secondterminal device requests performing the second handover scheme, and thehandover command further includes information on whether the secondterminal device is allowed to perform cell reselection.

If the second network device allows the second terminal device toreselect a cell, the handover command may further include information ofa cell to be accessed reselected by the second terminal device.

After receiving the handover command, the first network device may sendthe information of the cell to be accessed reselected by the secondterminal device to the second terminal device through the first terminaldevice.

In the implementation of the present disclosure, the network devicedetermines handover schemes of the two terminal devices by acquiringlink information of the Relay UE and link information of the Remote UE,to try to make the two terminal devices be located in a cell covered bya same network device after cell handover or cell reselection, thuseffective relay transmission may be continued between the Relay UE andthe Remote UE after the Relay UE and the Remote UE perform cellhandover.

FIG. 5 is a schematic flow chart of a handover method 500 according toan implementation of the present disclosure. The method may be performedby a first terminal device, which may be a Relay UE such as the terminaldevice 30 in FIG. 3 or a Remote UE such as the terminal device 40 inFIG. 3. As shown in FIG. 5, the handover method includes acts 510-530.

In 510, a first terminal device acquires measurement results of links,and the links include a link between the first terminal device and afirst network device and a link between the first network device and asecond terminal device.

In 520, the first terminal device sends the measurement results to thefirst network device, and the measurement results are used for the firstnetwork device to determine a first handover scheme of the firstterminal device.

In 530, the first terminal device receives a handover command andperforms the first handover scheme according to the handover command.

Optionally, the first terminal device is in a connected state.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE, or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

Specifically, when the second terminal device performs cell handover,the first terminal device acquires a measurement result of a linkbetween the first terminal device and the first network device andreports the measurement result to the first network device, so that thefirst network device determines a first handover scheme for the firstterminal device or may further determine a second handover scheme forthe second terminal device according to the measurement result of thelink between the first network device and the first terminal device anda measurement result of a link between the first network device and thesecond terminal device received from the second terminal device. Sincethe first network device acquires the measurement result of the linkbetween the first terminal device and the first network device and themeasurement result of the link between the second terminal device andthe first network device at the same time, the first network device maycomprehensively consider measurement results of multiple links whendetermining a handover scheme for the first terminal device, and try toselect a cell covered by the same network device as the second terminaldevice as a cell to be handed over to for the first terminal device.

Optionally, the measurement results of the links acquired by the firstterminal device may further include a measurement result of a linkbetween the first terminal device and the second terminal device.

In other words, the first terminal device may not only acquire ameasurement result of a link between the first network device and thefirst terminal device and a measurement result of a link between thefirst network device and the second terminal device, but also acquire ameasurement result of a link between the first terminal device and thesecond terminal device, and the first handover scheme and the secondhandover scheme are determined by comprehensively considering themeasurement results of the three links. Since a link condition betweenthe two terminal devices is considered, the two terminal devices may betried to be handed over to a cell covered by an identical network devicewhen necessary.

Optionally, the measurement result of a link includes a measurementresult of a link quality of the link and/or a measurement result of alink state of the link.

Optionally, in 510, the first terminal device acquires the measurementresults of the links, including: the first terminal device determines ameasurement result of a link between the first terminal device and thefirst network device, and receives a measurement result of a linkbetween the first network device and the second terminal device sent bythe second terminal device.

Further, the first terminal device acquires the measurement results ofthe links, further including: the first terminal device determines ameasurement result of a link between the first terminal device and thesecond terminal device; or the first terminal device receives ameasurement result of a link between the first terminal device and thesecond terminal device sent by the second terminal device.

Optionally, the first terminal device acquires the measurement resultsof the links, including: the first terminal device acquires ameasurement result of a link carried in an adaptation layer or a directconnection interface protocol stack PC5 sent by the second terminaldevice.

That is, information of interaction such as measurement results amongthe first terminal device, the second terminal device, and the firstnetwork device may be carried in an adaptation layer or in a signalingor data of an existing direct connection interface protocol stack PC5.

Optionally, in 520, the first handover scheme determined by the firstnetwork device for the first terminal device includes that the firstterminal device switches from a cell covered by the first network deviceto a cell covered by the second network device, or the first terminaldevice does not perform cell handover.

Optionally, if the first network device determines that a linkconnection between the first terminal device and the second terminaldevice is maintained according to the measurement result of the link,the first terminal device and the second terminal device are located ina cell covered by a same network device after the first terminal deviceperforms the first handover scheme.

Specifically, if the first network device determines that the linkconnection between the first terminal device and the second terminaldevice is maintained, for example, when the first network devicedetermines that the link connection between the first terminal deviceand the second terminal device should be maintained, or the linkconnection needs to be maintained continuously, the first handoverscheme determined by the first network device will enable the firstterminal device and the second terminal device after performing thesecond handover scheme to be located in a cell covered by an identicalnetwork device after the first terminal device performs the firsthandover scheme.

Optionally, if the first network device determines that the linkconnection between the first terminal device and the second terminaldevice is not maintained, the method further includes: the firstterminal device receives release indication information and releases thelink connection with the second terminal device according to the releaseindication information.

Optionally, the method further includes: the first terminal deviceacquires association information between the first terminal device andthe second terminal device, wherein the association information includesa pairing relationship or a connection relationship between the firstterminal device and the second terminal device; the first terminaldevice sends the association information to the first network device sothat the first network device determines a first handover schemeaccording to the association information and the measurement results.

Specifically, the first terminal device may send the pairingrelationship or connection relationship between the first terminaldevice and the second terminal device to the first network device, andthe first network device determines the first handover scheme accordingto the pairing relationship or connection relationship between the firstterminal device and the second terminal device and the measurementresults of the links. For example, if the first terminal device and thesecond terminal device are in a connection relationship and have datainteraction, the first network device will try to hand over the firstterminal device to a cell with the same coverage network as the secondterminal device according to the measurement results when determiningthe first handover scheme, although a signal intensity after handover isnot optimal.

Optionally, if the first handover scheme includes that the firstterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handovercommand received by the first terminal device in the act 530 furtherincludes a resource for cell handover of the first terminal device.

The handover command may be issued by the second network device to thefirst terminal device through the first network device, and the firstterminal device performs cell handover according to the resourceconfigured by the second network device for cell handover of the firstterminal device.

In the implementation of the present disclosure, the Relay UE and theRemote UE report their own link information to a network device, so thatthe network device may decide handover schemes of the two terminaldevices according to the link information of the Relay UE and the linkinformation of the Remote UE, to try to make the two terminal devices belocated in a cell covered by an identical network device after cellhandover or cell reselection, thus effective relay transmission may becontinued between the Relay UE and the Remote UE after the Relay UE andthe Remote UE perform cell handover.

FIG. 6 is a schematic flow chart of a handover method 600 according toan implementation of the present disclosure. The method may be performedby a second terminal device, which may be a Relay UE such as theterminal device 30 in FIG. 3 or a Remote UE such as the terminal device40 in FIG. 3. As shown in FIG. 6, the handover method includes acts610-630.

In 610, a second terminal device acquires a measurement result of alink, wherein the link includes a link between the second terminaldevice and a first network device.

In 620, the second terminal device sends the measurement result to thefirst network device through a first terminal device, and themeasurement result is used for the first network device to determine asecond handover scheme of the second terminal device.

In 630, the second terminal device receives a handover command andperforms the second handover scheme according to the handover command.

Optionally, the second terminal device is in an inactive state or anidle state.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE, or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

Specifically, when the second terminal device performs cell handover,the second terminal device acquires a measurement result of a linkbetween the second terminal device and the first network device, andreports the measurement result to the first network device through thefirst terminal device, so that the first network device determines asecond handover scheme for the second terminal device or may furtherdetermine a first handover scheme for the first terminal deviceaccording to the measurement result of the link between the firstnetwork device and the second terminal device and a measurement resultof a link between the first network device and the first terminal devicereceived from the first terminal device. Since the first network devicesimultaneously acquires the measurement result of the link between thesecond terminal device and the first network device and the measurementresult of the link between the first terminal device and the firstnetwork device, when the first network device determines the handoverscheme for the second terminal device, it may comprehensively considermeasurement results of multiple links and try to select a cell coveredby the same network device as the first terminal device for the secondterminal device as its reselected cell to be accessed.

Optionally, the measurement result of the link acquired by the secondterminal device may further include a measurement result of a linkbetween the second terminal device and the first terminal device.

Optionally, the measurement result of the link includes a measurementresult of a link quality of the link and/or a measurement result of alink state of the link.

Optionally, in 620, the second handover scheme determined by the firstnetwork device for the second terminal device includes that the secondterminal device reselects a cell covered by the second network device asa cell to be accessed, or the second terminal device does not performcell reselection.

Optionally, the second terminal device sends the measurement result tothe first network device through the first terminal device, including:the second terminal device sends the measurement result carried in anadaptation layer or a direct connection interface protocol stack PC5 tothe first network device through the first terminal device.

That is, information of interaction such as measurement results amongthe first terminal device, the second terminal device, and the firstnetwork device may be carried in an adaptation layer or in a signalingor data of an existing direct connection interface protocol stack PC5.

Optionally, if the first network device determines that a linkconnection between the first terminal device and the second terminaldevice is maintained, after the second terminal device performs thesecond handover scheme, the second terminal device and the firstterminal device are located in a cell covered by a same network device.

Specifically, if the first network device determines that the linkconnection between the first terminal device and the second terminaldevice is maintained, for example, when the first network devicedetermines that the link connection between the first terminal deviceand the second terminal device should be maintained, or the linkconnection needs to be maintained continuously, the second handoverscheme determined by the first network device will enable the secondterminal device and the first terminal device after performing the firsthandover scheme to be located in a cell covered by a same network deviceafter the second terminal device performs the second handover scheme.

Optionally, if the first network device determines that the linkconnection between the second terminal device and the first terminaldevice does not need to be maintained, the method further includes: thesecond terminal device receives release indication information andreleases the link connection with the first terminal device according tothe release indication information.

Optionally, if the second handover scheme includes that the secondterminal device reselects a cell covered by the second network device asa cell to be accessed, the handover command further includes informationof a cell to be accessed reselected by the second terminal device.

The handover command may be issued by the second network device to thesecond terminal device through the first network device or the firstterminal device. The second terminal device performs cell reselectionaccording to the received information of the cell and reselects a cellcovered by the second network device as a cell to be accessed.

Optionally, in 630, the second terminal device receives the handovercommand, including: the second terminal device receives the handovercommand sent by the first terminal device; or the second terminal devicereceives the handover command sent by the first network device through apaging message.

In the implementation of the present disclosure, a terminal device in anidle state or inactive state reports its own link information to anetwork device through a terminal device in a connected state, so thatthe network device may decide handover schemes of the two terminaldevices according to link information of the two terminal device, to tryto make the two terminal devices be located in a cell covered by a samenetwork device after cell handover or cell reselection, thus effectiverelay transmission may be continued between the Relay UE and the RemoteUE after the Relay UE and the Remote UE perform cell handover.

FIG. 7 is a schematic flow chart of a handover method 700 according toan implementation of the present disclosure. The method may be performedby a second network device, such as the network device 20 in FIG. 3. Asshown in FIG. 7, the handover method includes acts 710-720.

In 710, a second network device receives a handover request message sentby a first network device, and the handover request message is used forindicating that a first terminal device requests performing a firsthandover scheme and a second terminal device requests performing asecond handover scheme.

In 720, the second network device sends a handover command to the firstnetwork device according to the handover request message.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE, or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

Specifically, when the first terminal device and the second terminaldevice perform cell handover, the first network device determines afirst handover scheme for the first terminal device and a secondhandover scheme for the second terminal device according to measurementresults of links. Since the first network device simultaneously acquiresa measurement result of a link between the first terminal device and thefirst network device and a measurement result of a link between thesecond terminal device and the first network device (or may furthersimultaneously acquire a measurement result of a link between the firstterminal device and the second terminal device), when determiningrespective handover schemes for the first terminal device and the secondterminal device, the first network device may comprehensively considermeasurement results of multiple links and try to select a cell coveredby an identical network device as a cell to be handed over to or areselected cell to be accessed for the first terminal device and thesecond terminal device. When the first network device selects a cellcovered by the second network device as a cell to be handed over to or areselected cell to be accessed for both the first terminal device andthe second terminal device, the handover command (HO CMD) sent by thefirst network device and received by the second network devicesimultaneously indicates that the first terminal device requestsperforming the first handover scheme and the second terminal devicerequests performing the second handover scheme.

Optionally, if the first terminal device is in a connected state, thefirst handover scheme includes that the first terminal device is handedover from a cell covered by the first network device to a cell coveredby the second network device, or the first terminal device does notperform cell handover.

If the first terminal device is in an inactive state or an idle state,the first handover scheme includes that the first terminal devicereselects a cell covered by the second network device as a cell to beaccessed, or the first terminal device does not perform cellreselection;

If the second terminal device is in a connected state, the secondhandover scheme includes that the second terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device or a cell covered by another network device, orthe second terminal device does not perform cell handover;

If the second terminal device is in an inactive state or an idle state,the second handover scheme includes that the second terminal devicereselects a cell covered by the second network device or a cell coveredby another network device as a cell to be accessed, or the secondterminal device does not perform cell reselection.

Optionally, if the first handover scheme includes that the firstterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handovercommand includes a resource for cell handover of the first terminaldevice.

Optionally, if the second handover scheme includes that the secondterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handovercommand further includes a resource for cell handover of the secondterminal device.

Optionally, if the second handover scheme includes that the secondterminal device reselects a cell covered by the second network device asa cell to be accessed, the handover command further includes informationon whether the second terminal device is allowed to perform cellreselection.

In 720, the second network device may send a handover command to thefirst network device, thereby indicating a resource for cell handover orcell information of a cell to be reselected to the first terminal deviceand the second terminal device through the first network device.

In the implementation of the present disclosure, after receiving ahandover request message, a network device determines whether respectivehandover schemes of the Relay UE and the Remote UE are appropriate, andsimultaneously issues a handover command to the Relay UE and the RemoteUE, to try to make the two terminal devices be located in a cell coveredby the network device itself after the two terminal devices perform cellhandover or cell reselection, thus effective relay transmission may becontinued between the Relay UE and the Remote UE after the Relay UE andthe Remote UE perform cell handover.

Referring to FIGS. 8 and 9, the handover method of the implementation ofthe present disclosure will be described in detail with two detailedexamples. It should be understood that FIGS. 8 and 9 are only examples,and the implementations of the present disclosure are not limitedthereto.

FIG. 8 is a diagram of an interaction flow of a handover methodaccording to an implementation of the present disclosure. Both the firstterminal device and the second terminal device in FIG. 8 are in aconnected state. As shown in FIG. 8, the method includes acts 801-809.

In 801, a second terminal device sends a measurement result of a link ofthe second terminal device to a first network device.

The measurement result of the link of the second terminal deviceincludes a measurement result (e.g., link condition or link quality) ofa link between the second terminal device and the first network device.

Optionally, the second terminal device may send the measurement resultof the link of the second terminal device to the first network devicethrough a first terminal device.

In 802, a first terminal device sends measurement results of links ofthe first terminal device to the first network device.

The measurement results of the links of the first terminal deviceinclude a measurement result of a link between the first terminal deviceand the first network device and a measurement result of a link betweenthe first terminal device and the second terminal device.

At this time, the first terminal device may further send a pairingrelationship/connection relationship between the first terminal deviceand the second terminal device to the first network device.

In 803, the first network device determines a first handover scheme ofthe first terminal device and a second handover scheme of the secondterminal device.

The first network device may determine the first handover scheme of thefirst terminal device and the second handover scheme of the secondterminal device according to measurement results of links and a pairingrelationship/connection relationship between the first terminal deviceand the second terminal device.

The first handover scheme includes that the first terminal device ishanded over from a cell covered by the first network device to a cellcovered by the second network device, and the second handover schemeincludes that the second terminal device is handed over from a cellcovered by the first network device to a cell covered by the secondnetwork device.

In 804, the first network device sends a handover request message to thesecond network device.

The handover request message includes a context of the first terminaldevice and a context of the second terminal device, and/or includes apairing relationship/connection relationship between the first terminaldevice and the second terminal device.

In 805, the second network device sends a handover command to the firstnetwork device.

The handover command includes a resource for cell handover of the firstterminal device and a resource for cell handover of the second terminaldevice.

In 806, the first network device sends a first handover indicationmessage to the first terminal device.

The first handover indication message includes a resource for cellhandover of the first terminal device, and the first handover indicationmessage is used for instructing the first terminal device to perform thefirst handover scheme.

In 807, the first network device sends a second handover indicationmessage to the second terminal device.

The second handover indication message includes a resource for cellhandover of the second terminal device, and the second handoverindication message is used for instructing the second terminal device toperform the second handover scheme.

Optionally, the first network device may send second handover indicationmessage to the second terminal device through the first terminal device.

In 808, the first terminal device performs the first handover scheme tobe handed over to a cell covered by the second network device.

In 809, the second terminal device performs the second handover schemeto be handed over to a cell covered by the second network device.

If the first network device determines that a link connection betweenthe first terminal device and the second terminal device does not needto be or should not be or is not suitable for continuing to bemaintained, or a current condition of a signal intensity cannot bettermaintain the link connection between the first terminal device and thesecond terminal device, the first network device may further sendrelease indication information to the first terminal device and thesecond terminal device to indicate releasing of the link connectionbetween each other.

The release indication information may be sent to the first terminaldevice together through the first handover indication message and to thesecond terminal device together through the second handover indicationmessage.

FIG. 9 is a diagram of an interaction flow of a handover methodaccording to an implementation of the present disclosure. In FIG. 9, thefirst terminal device is in a connected state, and the second terminaldevice is in an inactive state or an idle state. As shown in FIG. 9, themethod includes acts 901-909.

In 901, a second terminal device sends a measurement result of a link ofthe second terminal device to a first network device through a firstterminal device.

The measurement result of the link of the second terminal deviceincludes a measurement result (e.g., link condition or link quality) ofa link between the second terminal device and the first network device.

In 902, the first terminal device sends measurement results of links ofthe first terminal device and a measurement result of a link of thesecond terminal device to the first network device.

The measurement results of the links of the first terminal deviceincludes a measurement result of a link between the first terminaldevice and the first network device and a measurement result of a linkbetween the first terminal device and the second terminal device.

At this time, the first terminal device may further send a pairingrelationship/connection relationship between the first terminal deviceand the second terminal device to the first network device.

In 903, the first network device determines a first handover scheme ofthe first terminal device and a second handover scheme of the secondterminal device.

The first network device may determine the first handover scheme of thefirst terminal device and the second handover scheme of the secondterminal device according to measurement results of links and a pairingrelationship/connection relationship between the first terminal deviceand the second terminal device.

The first handover scheme includes that the first terminal device ishanded over from a cell covered by the first network device to a cellcovered by the second network device, and the second handover schemeincludes that the second terminal device reselects a cell covered by thesecond network device as a cell to be accessed.

In 904, the first network device sends a handover request message to thesecond network device.

The handover request message includes a context of the first terminaldevice and a context of the second terminal device, and/or includes apairing relationship/connection relationship between the first terminaldevice and the second terminal device.

In 905, the second network device sends a handover command to the firstnetwork device.

The handover command includes a resource for cell handover of the firstterminal device and information on whether the second terminal device isallowed to perform cell reselection.

Assuming that the second network device allows the second terminaldevice to reselect a cell, i.e., allows the second terminal device todetermine a cell covered by the second network device as a cell to beaccessed, the handover command further includes cell information of thecell to be reselected by the second terminal device.

In 906, the first network device sends a first handover indicationmessage to the first terminal device.

The first handover indication message includes a resource for cellhandover of the first terminal device, and the first handover indicationmessage is used for instructing the first terminal device to perform thefirst handover scheme.

In 907, the first network device sends a handover indication message tothe second terminal device through the first terminal device.

The second handover indication message includes cell information of acell to be reselected by the second terminal device, and the secondhandover indication message is used for instructing the second terminaldevice to perform the second handover scheme.

In 908, the first terminal device performs the first handover scheme tobe handed over to a cell covered by the second network device.

In 909, the second terminal device performs the second handover schemeto reselect a cell covered by the second network device as a cell to beaccessed.

If the first network device determines that a link connection betweenthe first terminal device and the second terminal device does not needto be or should not be or is not suitable for continuing to bemaintained, or a current condition of a signal intensity cannot bettermaintain the link connection between the first terminal device and thesecond terminal device, the first network device may further sendrelease indication information to the first terminal device and thesecond terminal device to indicate releasing of the link connectionbetween each other.

The release indication information may be sent to the first terminaldevice together through the first handover indication message and to thesecond terminal device together through the second handover indicationmessage.

It should be understood that in various implementations of the presentdisclosure, sequence numbers of the various processes do not imply anorder of execution of the various processes, which should be determinedby their functions and internal logics, and should not constitute anylimitation on implementation processes of the implementations of thepresent disclosure.

FIG. 10 is a schematic block diagram of a network device 1000 accordingto an implementation of the present disclosure. As shown in FIG. 10, thenetwork device 1000 is a first network device and includes an acquiringunit 1010 and a determining unit 1020.

The acquiring unit is used for acquiring measurement results of links,wherein the links include a link between the first network device and afirst terminal device and a link between the first network device and asecond terminal device.

The determining unit is used for determining a first handover scheme ofthe first terminal device and/or a second handover scheme of the secondterminal device according to the measurement results acquired by theacquiring unit.

Therefore, the network device determines handover schemes of the twoterminal devices by acquiring link information of the Relay UE and linkinformation of the Remote UE, to try to make the two terminal devices belocated in a cell covered by a same network device after cell handoveror cell reselection, thus effective relay transmission may be continuedbetween the Relay UE and the Remote UE after the Relay UE and the RemoteUE perform cell handover.

Optionally, the links further include a link between the first terminaldevice and the second terminal device.

Optionally, the determining unit is specifically used for determiningthe first handover scheme and/or the second handover scheme according tostates of the first terminal device and the second terminal device, andthe measurement results.

Optionally, if the first terminal device is in a connected state, thefirst handover scheme includes that the first terminal device is handedover from a cell covered by the first network device to a cell coveredby the second network device, or the first terminal device does notperform cell handover.

If the first terminal device is in an inactive state or an idle state,the first handover scheme includes that the first terminal devicereselects a cell covered by the second network device as a cell to beaccessed, or the first terminal device does not perform cellreselection.

If the second terminal device is in a connected state, the secondhandover scheme includes that the second terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device or a cell covered by another network device, orthe second terminal device does not perform cell handover.

If the second terminal device is in an inactive state or an idle state,the second handover scheme includes that the second terminal devicereselects a cell covered by the second network device or a cell coveredby another network device as a cell to be accessed, or the secondterminal device does not perform cell reselection.

Optionally, the determining unit is specifically used for determiningwhether a link connection between the first terminal device and thesecond terminal device is maintained according to the measurementresults; determining the first handover scheme and/or the secondhandover scheme according to whether the link connection between thefirst terminal device and the second terminal device is maintained.

Optionally, if the first network device determines that the linkconnection between the first terminal device and the second terminaldevice is maintained, after the first terminal device performs the firsthandover scheme and the second terminal device performs the secondhandover scheme, the first terminal device and the second terminaldevice are located in a cell covered by a same network device.

Optionally, the first network device further includes a sending unit,and the determining unit is further used for determining whether a linkconnection between the first terminal device and the second terminaldevice is maintained according to the measurement results.

If the first network device determines that the link connection betweenthe first terminal device and the second terminal device is notmaintained, the sending unit is used for sending release indicationinformation to the first terminal device, and the release indicationinformation is used for instructing the first terminal device to releasethe link connection with the second terminal device.

Optionally, the acquiring unit is further used for acquiring associationinformation between the first terminal device and the second terminaldevice before the determining unit determines the first handover schemeof the first terminal device and/or the second handover scheme of thesecond terminal device according to the measurement results, wherein theassociation information includes a pairing relationship or a connectionrelationship between the first terminal device and the second terminaldevice.

The determining unit is specifically used for determining the firsthandover scheme and/or the second handover scheme according to theassociation information and the measurement results.

Optionally, if the first handover scheme includes that the firstterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the first networkdevice further includes a receiving unit, and the sending unit isfurther used for sending a handover request message to the secondnetwork device, wherein the handover request message is used forindicating that the first terminal device requests performing the firsthandover scheme.

The receiving unit is used for receiving a handover command sent by thesecond network device according to the handover request message, whereinthe handover command includes a resource for cell handover of the firstterminal device.

Optionally, the handover request message includes associationinformation between the first terminal device and the second terminaldevice.

Optionally, if the second handover scheme includes that the secondterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handoverrequest message is further used for indicating that the second terminaldevice requests performing the second handover scheme, and the handovercommand further includes a resource for cell handover of the secondterminal device.

Optionally, if the second handover scheme includes that the secondterminal device reselects a cell covered by the second network device ora cell covered by another network device as a cell to be accessed, thehandover request message is further used for indicating that the secondterminal device requests performing the second handover scheme, and thehandover command further includes information on whether the secondterminal device is allowed to perform cell reselection.

Optionally, if the second network device allows the second terminaldevice to perform cell reselection, the handover command furtherincludes information of a cell to be accessed reselected by the secondterminal device.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE; or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

Optionally, the measurement result of a link includes a measurementresult of a link quality of the link and/or a measurement result of alink state of the link.

Optionally, the acquiring unit is specifically used for receiving themeasurement results sent by the first terminal device; or receiving ameasurement result of a link between the first terminal device and thefirst network device sent by the first terminal device, and receiving ameasurement result of a link between the second terminal device and thefirst network device sent by the second terminal device.

Optionally, the acquiring unit is specifically used for receiving ameasurement result of a link between the first terminal device and thesecond terminal device sent by the first terminal device or the secondterminal device.

Optionally, the acquiring unit is specifically used for acquiring ameasurement result of a link carried in an adaptation layer or a directconnection interface protocol stack PC5 sent by the first terminaldevice or the second terminal device.

FIG. 11 is a schematic block diagram of a terminal device 1100 accordingto an implementation of the present disclosure. As shown in FIG. 11, theterminal device 1100 is a second terminal device, and the terminaldevice 1100 includes an acquiring unit 1110, a sending unit 1120, and aprocessing unit 1130.

The acquiring unit 1110 is used for acquiring measurement results oflinks, wherein the links includes a link between a first terminal deviceand a first network device, and a link between the first network deviceand a second terminal device.

The sending unit 1120 is used for sending the measurement resultsacquired by the acquiring unit 1110 to the first network device, whereinthe measurement results are used for the first network device todetermine a first handover scheme of the first terminal device.

The processing unit 1130 is used for receiving a handover command andperforming the first handover scheme according to the handover command.

Therefore, the Relay UE and the Remote UE report their own linkinformation to a network device, so that the network device may decidehandover schemes of the two terminal devices according to linkinformation of the Relay UE and the link information of the Remote UE,to try to make the two terminal devices be located in a cell covered bya same network device after cell handover or cell reselection, thuseffective relay transmission may be continued between the Relay UE andthe Remote UE after the Relay UE and the Remote UE perform cellhandover.

Optionally, the links further include a link between the first terminaldevice and the second terminal device.

Optionally, the first handover scheme includes that the first terminaldevice is handed over from a cell covered by the first network device toa cell covered by the second network device, or the first terminaldevice does not perform cell handover.

Optionally, if the first network device determines that a linkconnection between the first terminal device and the second terminaldevice is maintained, the first terminal device and the second terminaldevice are located in a cell covered by a same network device after thefirst terminal device performs the first handover scheme.

Optionally, if the first network device determines that the linkconnection between the first terminal device and the second terminaldevice is not maintained, the processing unit 1130 is further used forreceiving release indication information and release the link connectionwith the second terminal device according to the release indicationinformation.

Optionally, the acquiring unit 1110 is further used for acquiringassociation information between the first terminal device and the secondterminal device, wherein the association information includes a pairingrelationship or a connection relationship between the first terminaldevice and the second terminal device.

The sending unit 1120 is further used for sending the associationinformation to the first network device so that the first network devicedetermines the first handover scheme according to the associationinformation and the measurement results.

Optionally, if the first handover scheme includes that the firstterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handovercommand further includes a resource for cell handover of the firstterminal device.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE; or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

Optionally, the measurement result of a link includes a measurementresult of a link quality of the link and/or a measurement result of alink state of the link.

Optionally, the acquiring unit 1110 is specifically used for determininga measurement result of a link between the first terminal device and thefirst network device, and receiving a measurement result of a linkbetween the first network device and the second terminal device sent bythe second terminal device.

Optionally, the acquiring unit 1110 is specifically used for determininga measurement result of a link between the first terminal device and thesecond terminal device; or receiving a measurement result of a linkbetween the first terminal device and the second terminal device sent bythe second terminal device.

Optionally, the acquiring unit 1110 is specifically used for acquiring ameasurement result of a link carried in an adaptation layer or a directconnection interface protocol stack PC5 sent by the second terminaldevice.

FIG. 12 is a schematic block diagram of a terminal device 1200 accordingto an implementation of the present disclosure. As shown in FIG. 12, theterminal device 1200 is a second terminal device and includes anacquiring unit 1210, a sending unit 1220, and a processing unit 1230.

The acquiring unit 1210 is used for acquiring a measurement result of alink, wherein the link includes a link between the second terminaldevice and a first network device.

The sending unit 1220 is used for sending the measurement resultacquired by the acquiring unit 1210 to the first network device throughthe first terminal device, the measurement result being used by thefirst network device to determine a second handover scheme of the secondterminal device.

The processing unit 1230 is used for receiving a handover command andperforming the second handover scheme according to the handover command.

Therefore, a terminal device in an idle state or inactive state reportsits own link information to a network device through a terminal devicein a connected state, so that the network device may decide handoverschemes of the two terminal devices according to link information of thetwo terminal device, to try to make the two terminal devices be locatedin a cell covered by a same network device after cell handover or cellreselection, thus effective relay transmission may be continued betweenthe Relay UE and the Remote UE after the Relay UE and the Remote UEperform cell handover.

Optionally, the link further includes a link between the first terminaldevice and the second terminal device.

Optionally, the second handover scheme includes that the second terminaldevice reselects a cell covered by the second network device as a cellto be accessed, or the second terminal device does not perform cellreselection.

Optionally, if the first network device determines that a linkconnection between the first terminal device and the second terminaldevice is maintained, after the second terminal device performs thesecond handover scheme, the second terminal device and the firstterminal device are located in a cell covered by a same network device.

Optionally, if the first network device determines that a linkconnection between the second terminal device and the first terminaldevice does not need to be maintained, the processing unit 1230 isfurther used for receiving release indication information and releasingthe link connection with the first terminal device according to therelease indication information.

Optionally, if the second handover scheme includes that the secondterminal device reselects a cell covered by the second network device asa cell to be accessed, the handover command further includes informationof a cell to be accessed reselected by the second terminal device.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE; or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

Optionally, the measurement result of the link includes a measurementresult of a link quality of the link and/or a measurement result of alink state of the link.

Optionally, the sending unit 1220 is specifically used for sending themeasurement result carried in an adaptation layer or a direct connectioninterface protocol stack PC5 to the first network device through thefirst terminal device.

Optionally, the processing unit 1230 is specifically used for receivingthe handover command sent by the first terminal device and performingthe second handover scheme according to the handover command; orreceiving the handover command sent by the first network device througha paging message and performing the second handover scheme according tothe handover command.

FIG. 13 is a schematic block diagram of a network device 1300 accordingto an implementation of the present disclosure. As shown in FIG. 13, thenetwork device 1300 is a second network device and includes a receivingunit 1310 and a sending unit 1320.

The receiving unit 1310, used for receiving a handover request messagesent by a first network device, wherein the handover request message isused for indicating that a first terminal device requests performing afirst handover scheme and the second terminal device requests performinga second handover scheme.

The sending unit 1320 is used for sending a handover command to thefirst network device according to the handover request message receivedby the receiving unit 1310.

Therefore, after receiving a handover request message, a network devicedetermines whether respective handover schemes of the Relay UE and theRemote UE are appropriate, and simultaneously issues a handover commandto the Relay UE and the Remote UE, to try to make the two terminaldevices be located in a cell covered by the network device itself afterthe two terminal devices perform cell handover or cell reselection, thuseffective relay transmission may be continued between the Relay UE andthe Remote UE after the Relay UE and the Remote UE perform cellhandover.

Optionally, if the first terminal device is in a connected state, thefirst handover scheme includes that the first terminal device is handedover from a cell covered by the first network device to a cell coveredby the second network device, or the first terminal device does notperform cell handover.

If the first terminal device is in an inactive state or an idle state,the first handover scheme includes that the first terminal devicereselects a cell covered by the second network device as a cell to beaccessed, or the first terminal device does not perform cellreselection.

If the second terminal device is in a connected state, the secondhandover scheme includes that the second terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device or a cell covered by another network device, orthe second terminal device does not perform cell handover.

If the second terminal device is in an inactive state or an idle state,the second handover scheme includes that the second terminal devicereselects a cell covered by the second network device or a cell coveredby another network device as a cell to be accessed, or the secondterminal device does not perform cell reselection.

Optionally, if the first handover scheme includes that the firstterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handovercommand further includes a resource for cell handover of the firstterminal device.

Optionally, if the second handover scheme includes that the secondterminal device is handed over from a cell covered by the first networkdevice to a cell covered by the second network device, the handovercommand further includes a resource for cell handover of the secondterminal device.

Optionally, if the second handover scheme includes that the secondterminal device reselects a cell covered by the second network device asa cell to be accessed, the handover command further includes informationon whether the second terminal device is allowed to perform cellreselection.

Optionally, if the second network device allows the second terminaldevice to perform cell reselection, the handover command furtherincludes information of a cell to be accessed reselected by the secondterminal device.

Optionally, the first terminal device is a Relay UE and the secondterminal device is a Remote UE; or the first terminal device is a RemoteUE and the second terminal device is a Relay UE.

FIG. 14 is a schematic diagram of structure of a network device 1400according to an implementation of the present disclosure. As shown inFIG. 14, the network device includes a processor 1410, a transceiver1420, and a memory 1430, wherein the processor 1410, the transceiver1420, and the memory 1430 communicate with each other through aninternal connection path. The memory 1430 is used for storinginstructions, and the processor 1410 is used for executing instructionsstored in the memory 1430 to control the transceiver 1420 to send orreceive signals.

Optionally, the processor 1410 may call the program codes stored in thememory 1430 to perform corresponding operations of network device in themethod 400 shown in FIG. 4, which will not be described here repeatedlyfor brevity.

It should be understood that in the implementation of the presentdisclosure, the processor 1410 may be a Central Processing Unit (CPU),or the processor 1410 may be other general purpose processor, digitalsignal processor (DSP), application specific integrated circuit (ASIC),Field Programmable Gate Array (FPGA), or other programmable logicdevice, discrete gate or transistor logic device, discrete hardwarecomponent, etc. The general purpose processor may be a microprocessor,or the processor may be any conventional processor or the like.

The memory 1430 may include a read only memory and a random accessmemory and provide instructions and data to the processor 1410. Aportion of memory 1430 may further include a non-volatile random accessmemory. For example, the memory 1430 may further store device typeinformation.

In an implementation process, the acts of the methods described abovemay be accomplished by integrated logic circuits of hardware in theprocessor 1410 or instructions in a form of software. The acts of thepositioning method disclosed in the implementation of the presentdisclosure may be directly accomplished by an execution of a hardwareprocessor or accomplished by a combination of hardware and softwaremodules in the processor 1410. The software modules may be located intypical storage medium in the art, such as a random access memory, flashmemory, read-only memory, programmable read-only memory or electricallyerasable programmable memory, or register. The storage medium is locatedin the memory 1430, and the processor 1410 reads the information in thememory 1430 and accomplishes the acts of the above method in combinationwith its hardware. In order to avoid repetition, it will not bedescribed in detail here.

The network device 1400 according to the implementation of the presentdisclosure may correspond to the network device for executing the method400 in the method 400 and the network device 1000 according to theimplementation of the present disclosure, and various units or modulesin the network device 1400 are respectively used for executing variousactions or processing processes executed by the network device in themethod 400. Here, in order to avoid redundancy, detailed descriptionthereof is omitted.

FIG. 15 is a schematic diagram of structure of a terminal device 1500according to an implementation of the present disclosure. As shown inFIG. 15, the terminal device includes a processor 1510, a transceiver1520, and a memory 1530, wherein the processor 1510, the transceiver1520, and the memory 1530 communicate with each other through aninternal connection path. The memory 1530 is used for storinginstructions, and the processor 1510 is used for executing instructionsstored in the memory 1530 to control the transceiver 1520 to send orreceive signals.

Optionally, the processor 1510 may call the program codes stored in thememory 1530 to perform corresponding operations of terminal device inthe method 500 shown in FIG. 5, which will not be described hererepeatedly for brevity.

It should be understood that, in an implementation of the presentdisclosure, the processor 1510 may be a central processing unit (CPU),or the processor 1510 may be other general purpose processor, a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a field programmable gate array (FPGA), or other programmablelogic device, a discrete gate or a transistor logic device, or adiscrete hardware component, etc. The general purpose processor may be amicroprocessor, or the processor may be any conventional processor orthe like.

The memory 1530 may include a read only memory and a random accessmemory and provide instructions and data to the processor 1510. Aportion of memory 1530 may further include a non-volatile random accessmemory. For example, the memory 1530 may further store device typeinformation.

In an implementation process, the acts of the methods described abovemay be accomplished by integrated logic circuits of hardware in theprocessor 1510 or instructions in a form of software. The acts of thepositioning method disclosed in the implementation of the presentdisclosure may be directly accomplished by an execution of a hardwareprocessor or accomplished by a combination of hardware and softwaremodules in the processor 1510. The software modules may be located intypical storage medium in the art, such as a random access memory, flashmemory, read-only memory, programmable read-only memory or electricallyerasable programmable memory, or register. The storage medium is locatedin the memory 1530, and the processor 1510 reads the information in thememory 1530 and accomplishes the acts of the above method in combinationwith its hardware. In order to avoid repetition, it will not bedescribed in detail here.

The terminal device 1500 according to the implementation of the presentdisclosure may correspond to the terminal device for executing themethod 500 in the method 500 and the terminal device 1100 according tothe implementation of the present disclosure, and various units ormodules in the terminal device 1500 are respectively used for executingvarious actions or processing processes executed by the terminal devicein the method 500. Here, in order to avoid redundancy, detaileddescription thereof is omitted.

FIG. 16 is a schematic diagram of structure of a terminal device 1600according to an implementation of the present disclosure. As shown inFIG. 16, the terminal device includes a processor 1610, a transceiver1620, and a memory 1630, wherein the processor 1610, the transceiver1620, and the memory 1630 communicate with each other through aninternal connection path. The memory 1630 is used for storinginstructions, and the processor 1610 is used for executing instructionsstored in the memory 1630 to control the transceiver 1620 to send orreceive signals.

Optionally, the processor 1610 may call the program codes stored in thememory 1630 to perform corresponding operations of terminal device inthe method 600 shown in FIG. 6, which will not be described hererepeatedly for brevity.

It should be understood that, in an implementation of the presentdisclosure, the processor 1610 may be a central processing unit (CPU),or the processor 1610 may be other general purpose processor, a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a field programmable gate array (FPGA), or other programmablelogic device, a discrete gate or a transistor logic device, or adiscrete hardware component, etc. The general purpose processor may be amicroprocessor, or the processor may be any conventional processor orthe like.

The memory 1630 may include a read only memory and a random accessmemory and provide instructions and data to the processor 1610. Aportion of memory 1630 may further include a non-volatile random accessmemory. For example, the memory 1630 may further store device typeinformation.

In an implementation process, the acts of the methods described abovemay be accomplished by integrated logic circuits of hardware in theprocessor 1610 or instructions in a form of software. The acts of thepositioning method disclosed in the implementation of the presentdisclosure may be directly accomplished by an execution of a hardwareprocessor or accomplished by a combination of hardware and softwaremodules in the processor 1610. The software modules may be located intypical storage medium in the art, such as a random access memory, flashmemory, read-only memory, programmable read-only memory or electricallyerasable programmable memory, or register. The storage medium is locatedin the memory 1630, and the processor 1610 reads the information in thememory 1630 and accomplishes the acts of the above method in combinationwith its hardware. In order to avoid repetition, it will not bedescribed in detail here.

The terminal device 1600 according to the implementation of the presentdisclosure may correspond to the terminal device for executing themethod 600 in the method 600 and the terminal device 1700 according tothe implementation of the present disclosure, and various units ormodules in the terminal device 1600 are respectively used for executingvarious actions or processing processes executed by the terminal devicein the method 600. Here, in order to avoid redundancy, detaileddescription thereof is omitted.

FIG. 17 is a schematic diagram of structure of a network device 1700according to an implementation of the present disclosure. As shown inFIG. 17, the network device includes a processor 1710, a transceiver1720, and a memory 1730, wherein the processor 1710, the transceiver1720, and the memory 1730 communicate with each other through aninternal connection path. The memory 1730 is used for storinginstructions, and the processor 1710 is used for executing instructionsstored in the memory 1730 to control the transceiver 1720 to send orreceive signals.

Optionally, the processor 1710 may call the program codes stored in thememory 1730 to perform corresponding operations of network device in themethod 700 shown in FIG. 7, which will not be described here repeatedlyfor brevity.

It should be understood that in the implementation of the presentdisclosure, the processor 1710 may be a Central Processing Unit (CPU),or the processor 1710 may be other general purpose processor, digitalsignal processor (DSP), application specific integrated circuit (ASIC),Field Programmable Gate Array (FPGA), or other programmable logicdevice, discrete gate or transistor logic device, discrete hardwarecomponent, etc. The general purpose processor may be a microprocessor,or the processor may be any conventional processor or the like.

The memory 1730 may include a read only memory and a random accessmemory and provide instructions and data to the processor 1710. Aportion of memory 1730 may further include a non-volatile random accessmemory. For example, the memory 1730 may further store device typeinformation.

In an implementation process, the acts of the methods described abovemay be accomplished by integrated logic circuits of hardware in theprocessor 1710 or instructions in a form of software. The acts of thepositioning method disclosed in the implementation of the presentdisclosure may be directly accomplished by an execution of a hardwareprocessor or accomplished by a combination of hardware and softwaremodules in the processor 1710. The software modules may be located intypical storage medium in the art, such as a random access memory, flashmemory, read-only memory, programmable read-only memory or electricallyerasable programmable memory, or register. The storage medium is locatedin the memory 1730, and the processor 1710 reads the information in thememory 1730 and accomplishes the acts of the above method in combinationwith its hardware. In order to avoid repetition, it will not bedescribed in detail here.

The network device 1700 according to the implementation of the presentdisclosure may correspond to the network device for executing the method700 in the method 700 and the network device 1300 according to theimplementation of the present disclosure, and various units or modulesin the network device 1700 are respectively used for executing variousactions or processing processes executed by the network device in themethod 700. Here, in order to avoid redundancy, detailed descriptionthereof is omitted.

FIG. 18 is a schematic diagram of structure of a system chip accordingto an implementation of the present disclosure. The system chip 1800 ofFIG. 18 includes an input interface 1801, an output interface 1802, atleast one processor 1803, and a memory 1804. The input interface 1801,the output interface 1802, the processor 1803, and the memory 1804 areconnected to each other through an internal connection path. Theprocessor 1803 is used for executing codes in the memory 1804.

Optionally, the processor 1803 may implement the method 400 executed bythe network device in the method implementation when the codes areexecuted. For the sake of brevity, it will not be repeated here.

Optionally, the processor 1803 may implement the method 500 executed bythe terminal device in the method implementation when the codes areexecuted. For the sake of brevity, it will not be repeated here.

Optionally, the processor 1803 may implement the method 600 executed bythe terminal device in the method implementation when the codes areexecuted. For the sake of brevity, it will not be repeated here.

Optionally, the processor 1803 may implement the method 700 executed bythe network device in the method implementation when the codes areexecuted. For the sake of brevity, it will not be repeated here.

Those of ordinary skill in the art will recognize that the exemplaryelements and algorithm acts described in connection with theimplementations disclosed herein may be implemented in electronichardware, or a combination of computer software and electronic hardware.Whether these functions are implemented in hardware or software dependson the specific application and design constraints of the technicalsolution. Skilled artisans may use different methods to implement thedescribed functions in respect to each particular application, but suchimplementation should not be considered to be beyond the scope of thepresent disclosure.

Those skilled in the art may clearly understand that for convenience andconciseness of description, the specific working processes of thesystem, apparatus and unit described above may refer to thecorresponding processes in the aforementioned method implementations andwill not be described here.

In several implementations provided by the present disclosure, it shouldbe understood that the disclosed systems, apparatuses and methods may beimplemented in other ways. For example, the apparatus implementationdescribed above is only illustrative, for example, the division of theunit is only a logical function division, and there may be other ways ofdivision in actual implementation, for example, multiple units orcomponents may be combined or integrated into another system, or somefeatures may be ignored or not executed. On the other hand, the mutualcoupling or direct coupling or communication connection shown ordiscussed may be indirect coupling or communication connection throughsome interface, apparatus or unit, and may be in electrical, mechanicalor other forms.

The unit described as a separate component may or may not be physicallyseparated, and the component shown as a unit may or may not be aphysical unit, i.e., may be located in one place or may be distributedover multiple network units. Some or all of the units may be selectedaccording to actual needs to achieve the purpose of the implementations.

In addition, various functional units in various implementations of thepresent disclosure may be integrated in one processing unit, or thevarious units may be physically present separately, or two or more unitsmay be integrated in one unit.

The functions may be stored in a computer readable storage medium ifimplemented in a form of software functional units and sold or used as aseparate product. Based on this understanding, the technical solution ofthe present disclosure, in essence, or the part contributing to theprior art, or the part of the technical solution, may be embodied in theform of a software product stored in a storage medium, including anumber of instructions for causing a computer device (which may be apersonal computer, a server, or a network device) to perform all or partof the acts of the method described in various implementations of thepresent disclosure. The aforementioned storage medium include a U disk,mobile hard disk, read-only memory (ROM), random access memory (RAM),magnetic disk or optical disk and other media that may store programcodes.

What are described above are merely exemplary implementations of thepresent disclosure, but the protection scope of the present disclosureis not limited thereto. Any variation or substitution that may be easilyconceived by a person skilled in the art within the technical scopedisclosed by the present disclosure shall be included within theprotection scope of the present disclosure. Therefore, the protectionscope of the implementations of the present disclosure should be basedon the protection scope of the claims.

1. A method for handover, comprising: acquiring, by a first networkdevice, measurement results of links, wherein the links comprise a linkbetween the first network device and a first terminal device and a linkbetween the first network device and a second terminal device; anddetermining, by the first network device, at least one of a firsthandover scheme of the first terminal device or a second handover schemeof the second terminal device according to the measurement results. 2.The method according to claim 1, wherein the links further comprise alink between the first terminal device and the second terminal device.3. The method according to claim 1, wherein determining, by the firstnetwork device, at least one of the first handover scheme of the firstterminal device or the second handover scheme of the second terminaldevice according to the measurement results, comprises: determining, bythe first network device, at least one of the first handover scheme orthe second handover scheme according to states of the first terminaldevice and the second terminal device, and the measurement results. 4.The method according to claim 3, wherein when the first terminal deviceis in a connected state, the first handover scheme comprises that thefirst terminal device is handed over from a cell covered by the firstnetwork device to a cell covered by a second network device, or thefirst terminal device does not perform cell handover; when the firstterminal device is in an inactive state or an idle state, the firsthandover scheme comprises that the first terminal device reselects acell covered by the second network device as a cell to be accessed, orthe first terminal device does not perform cell reselection; when thesecond terminal device is in a connected state, the second handoverscheme comprises that the second terminal device is handed over from acell covered by the first network device to a cell covered by the secondnetwork device or a cell covered by another network device, or thesecond terminal device does not perform cell handover; and when thesecond terminal device is in an inactive state or an idle state, thesecond handover scheme comprises that the second terminal devicereselects a cell covered by the second network device or a cell coveredby another network device as a cell to be accessed, or the secondterminal device does not perform cell reselection.
 5. The methodaccording to claim 1, wherein determining, by the first network device,at least one of the first handover scheme of the first terminal deviceor the second handover scheme of the second terminal device according tothe measurement results, comprises: determining, by the first networkdevice, whether a link connection between the first terminal device andthe second terminal device is maintained according to the measurementresults; and determining, by the first network device, at least one ofthe first handover scheme or the second handover scheme according towhether the link connection between the first terminal device and thesecond terminal device is maintained.
 6. The method according to claim5, wherein if the first network device determines that the linkconnection between the first terminal device and the second terminaldevice is maintained, after the first terminal device performs the firsthandover scheme and the second terminal device performs the secondhandover scheme, the first terminal device and the second terminaldevice are located in a cell covered by a same network device.
 7. Themethod according to claim 1, wherein the method further comprises:determining, by the first network device, whether a link connectionbetween the first terminal device and the second terminal device ismaintained according to the measurement results; and if the firstnetwork device determines that the link connection between the firstterminal device and the second terminal device is not maintained, themethod further comprises: sending, by the first network device, releaseindication information to the first terminal device, wherein the releaseindication information is used for instructing the first terminal deviceto release the link connection with the second terminal device.
 8. Themethod according to claim 1, wherein before the first network devicedetermines at least one of the first handover scheme of the firstterminal device or the second handover scheme of the second terminaldevice according to the measurement results, the method furthercomprises: acquiring, by the first network device, associationinformation between the first terminal device and the second terminaldevice, wherein the association information comprises a pairingrelationship or a connection relationship between the first terminaldevice and the second terminal device; and determining, by the firstnetwork device, at least one of the first handover scheme of the firstterminal device or the second handover scheme of the second terminaldevice according to the measurement results, comprises: determining, bythe first network device, at least one of the first handover scheme orthe second handover scheme according to the association information andthe measurement results.
 9. The method according to claim 1, wherein ifthe first handover scheme comprises that the first terminal device ishanded over from a cell covered by the first network device to a cellcovered by a second network device, the method further comprises:sending, by the first network device, a handover request message to thesecond network device, wherein the handover request message is used forindicating that the first terminal device requests performing the firsthandover scheme; and receiving, by the first network device, a handovercommand sent by the second network device according to the handoverrequest message, wherein the handover command comprises a resource forcell handover of the first terminal device.
 10. The method according toclaim 9, wherein the handover request message comprises associationinformation between the first terminal device and the second terminaldevice.
 11. The method according to claim 9, wherein if the secondhandover scheme comprises that the second terminal device is handed overfrom a cell covered by the first network device to a cell covered by thesecond network device, the handover request message is further used forindicating that the second terminal device requests performing thesecond handover scheme, and the handover command further comprises aresource for cell handover of the second terminal device.
 12. The methodaccording to claim 10, wherein if the second handover scheme comprisesthat the second terminal device reselects a cell covered by the secondnetwork device or a cell covered by another network device as a cell tobe accessed, the handover request message is further used for indicatingthat the second terminal device requests performing the second handoverscheme, and the handover command further comprises information onwhether the second terminal device is allowed to perform cellreselection.
 13. The method according to claim 12, wherein if the secondnetwork device allows the second terminal device to perform cellreselection, the handover command further comprises information of thecell to be accessed reselected by the second terminal device. 14.(canceled)
 15. (canceled)
 16. The method according to claim 1, whereinacquiring, by the first network device, the measurement results of thelinks, comprises: receiving, by the first network device, themeasurement results sent by the first terminal device; or receiving, bythe first network device, a measurement result of a link between thefirst terminal device and the first network device sent by the firstterminal device, and receiving a measurement result of a link betweenthe second terminal device and the first network device sent by thesecond terminal device.
 17. The handover method according to claim 16,wherein acquiring, by the first network device, the measurement resultsof the links, comprises: receiving, by the first network device, ameasurement result of a link between the first terminal device and thesecond terminal device sent by the first terminal device or the secondterminal device.
 18. (canceled)
 19. A handover method, comprising:acquiring, by a first terminal device, measurement results of links,wherein the links comprise a link between the first terminal device anda first network device and a link between the first network device and asecond terminal device; sending, by the first terminal device, themeasurement results to the first network device, wherein the measurementresults are used for the first network device to determine a firsthandover scheme of the first terminal device; and receiving, by thefirst terminal device, a handover command and performing the firsthandover scheme according to the handover command. 20-23. (canceled) 24.The method according to claim 19, wherein the method further comprises:maintaining, by the first terminal device, association informationbetween the first terminal device and the second terminal device,wherein the association information comprises a pairing relationship ora connection relationship between the first terminal device and thesecond terminal device; and sending, by the first terminal device, theassociation information to the first network device, for the firstnetwork device to determine the first handover scheme according to theassociation information and the measurement results. 25-27. (canceled)28. The method according to claim 19, wherein acquiring, by the firstterminal device, the measurement results of the links, comprises:determining, by the first terminal device, a measurement result of alink between the first terminal device and the first network device, andreceiving a measurement result of a link between the first networkdevice and the second terminal device sent by the second terminaldevice. 29-30. (canceled)
 31. A method for handover, comprising:acquiring, by a second terminal device, a measurement result of a link,wherein the link comprises a link between the second terminal device anda first network device; sending, by the second terminal device, themeasurement result to the first network device through a first terminaldevice, wherein the measurement result is used for the first networkdevice to determine a second handover scheme of the second terminaldevice; and receiving, by the second terminal device, a handover commandand performing the second handover scheme according to the handovercommand. 32-39. (canceled)
 40. The method according to claim 31, whereinreceiving, by the second terminal device, the handover command,comprises: receiving, by the second terminal device, the handovercommand sent by the first terminal device; or receiving, by the secondterminal device, the handover command sent by the first network devicethrough a paging message. 41-94. (canceled)